It’s quickly becoming a rite of autumn: The leaves change color, the harvest comes in and UCLA starts to turn its season around after disappointing early in October.

Perhaps it’s a bit too soon to definitively make that claim about the Bruins in 2015. But Thursday night’s 40–24 win over No. 20 Cal marks the third straight year that they’ve answered back-to-back conference losses with a much needed Pac-12 win.

What looked early on to be an offensive duel between the Josh Rosen-led Bruins and the Jared Goff-led Bears turned into a beatdown. UCLA’s maligned defense stepped up, and Cal had no answer for Rosen, who was in complete control of the offense all night.

Loaded with talent and boasting a potential difference-maker at quarterback, UCLA was hailed as a playoff contender and Pac-12 title favorite when Rosen came out hot to begin his college career. But after a commanding 4–0 start that moved them up to No. 7 in the AP poll, the Bruins were exposed in embarrassing losses to Arizona State and Stanford. The Sun Devils and Cardinal shredded UCLA’s run defense, and penalties and poor play combined to sink the offense. Some of the defensive issues were understandable given the litany of injuries on that side of the ball—defensive lineman Eddie Vanderdoes, linebacker Myles Jack and cornerback Fabian Moreau all suffered season-ending injuries—but more depth was expected of a team that returned eight defensive starters from last year.

With its back against the wall, UCLA showed a fight that was lacking for the past two weeks. It definitely helped that Cal doesn’t have the power running threat that Arizona State's Kalen Ballage and Stanford's Christian McCaffrey brought, but stopping Goff and the Bear Raid is no easy task. The Bruins managed to do so by playing much better against the run, pressuring Goff and looking fantastic and physical in the back end. Meanwhile, Rosen & Co. were clinical most of the night offensively.

It wasn’t a perfect performance. There were still plenty of costly penalties, and UCLA settled for field goals in the red zone too often, but that’s nitpicking in a game like this. The bigger bad news: Running back Paul Perkins, wide receiver Devin Fuller and leading tackler Isaako Savaiinaea all left with injuries, adding to an already extensive list. Perkins’s extended absence would be especially impactful as the junior led the Pac-12 in rushing last season and his backup, Nate Starks, already missed Thursday's game after suffering a head injury against Stanford.

Still, the win over Cal means the Bruins have a shot at a Pac-12 South title if they can win out and get some help. While frustration has to be building that they can’t seem to put it all together for a whole season, they can still have a successful year.

2. Cal’s defense, and the Bears at large, were exposed

The key to Cal’s supposed ascension this season was an improved defense, with the unit ranking 72nd in the country entering the UCLA game after languishing among the dregs of the FBS the past few seasons. The Bears' defense hadn’t looked like world-beaters this year, but it did look better.

And then Thursday happened. Cal couldn’t stop UCLA, and it was clear from the opening drive, when Perkins had consecutive runs of 12, 12, six and 11 yards to get the Bruins down the field in a hurry. That drive kicked off seven straight scoring marches. Five of them came before the end of the first half, capped by a school-record 60-yard field goal by kicker Ka'imi Fairbairn to give UCLA a 26–10 halftime lead. Its touchdown on the opening drive of the second half extended the lead to 33–10 and essentially iced the game.

UCLA’s running game was productive, especially before Perkins exited, and Rosen (more on him below) was sensational. The Bears entered Thursday’s game leading the nation with 21 takeaways but had just one against the Bruins: a fumble recovery when the game was already decided. Cal’s defensive backs got their hands on multiple would-be interceptions but couldn’t hold on to any of them. Had the defense played up to its usual opportunistic ways, the game could’ve gone much differently. As it was, the Bears gave up 573 yards and 40 points.

After starting 5–0 and looking primed for a breakthrough season, Cal is suddenly staring at a potential second-half swoon. If the defense continues to struggle and Goff can’t make up for it with some heroics, it’s a legitimate possibility the Bears sink to 6–6 by falling to USC, Oregon, Stanford and Arizona State. Even a 7–5 finish, a two-game improvement over 2014, would feel like something of a disappointment given the way the season began. It’s too early to close the book on Cal, but after this result it’s still up in the air whether the program has taken a step forward.

3. Rosen looks like a phenom again in outdueling Goff

Both signal-callers are ultra-talented. Goff could very well be the top quarterback taken in next spring’s NFL draft, and while Rosen is at least three years away from being eligible, his early results indicate he could be the first selected when he turns pro, too. But when comparing the two, you’d expect Goff to be at a higher level given his experience and greater polish.

That may prove true over the course of the season as Rosen has his ups and downs, but it certainly wasn’t the case Thursday. Rosen was the best player on the field, and his stats bear that out: a school-record 34 completions on 47 attempts for 399 yards with three touchdowns and zero interceptions. Rosen showed complete command of the offense all night. On the Bruins’ early drives, he took what the Cal defense gave him, settling for shorter completions to steadily move UCLA down the field. As the game wore on, he took more deep shots, making several throws that were worthy of double-takes because of their power and precision. All night he was poised, and he consistently made the right decisions.

Goff wasn’t bad, as he completed 32 of 53 attempts for 295 yards with three touchdowns and zero interceptions. Unlike Rosen, he didn’t have a running game to help take pressure off him, and he faced a UCLA defense that generated a much more effective past rush (the Bruins sacked Goff five times). Still, for a player of his caliber, it's reasonable to expect Goff to be able to raise the play of those around him, and after throwing five interceptions against Utah last time out, Goff failed to do so for the second straight game.

Instead it was Rosen raising his game. We’ve already seen some inconsistency from the true freshman, and that will likely continue, especially if he’s missing weapons like Perkins and Fuller. But Rosen again showed Thursday why he has the potential to someday be the best passer in college football.